1. Mell, P.M., Grance, T.: The NIST definition of cloud computing. Spec. Publ. (NIST SP) 6(9), 145–300 (2011)
2. Tabrizchi, H., Rafsanjani, M.K.: A survey on security challenges in cloud computing: issues, threats, and solutions. In: Proceedings of the 2018 ACM Conference on Computer and Communications Security, pp. 26–31, ACM, Raleigh, NC, USA (2018)
3. Singh, M.: Virtualization in cloud computing—a study. Nethost sensor: investigating the capture of end-to-end encrypted intrusive data. Comput. Secur. 25(6), pp. 205–251 (2020)
4. Bamiah, M.A., Brohi, S.N.: Towards intrusion detection for encrypted networks. In: Proceedings of the 2017 International Conference on Availability, Reliability and Security, IEEE, pp. 540–545, Fukuoka, Japan (2017)
5. Lee, J.H., Kim, J.K.K.: A new approach for the security of VPN. In: Proceedings of the 2nd International Conference on Information and Communication Technology for Competitive Strategies ICTCS’17, vol. 13, pp. 1–5, ACM (2017)